We had a simular problem, it was the P2 air pressure sensor on the top of the engine. Where it had sat for a while a small amount of corrosion built up therefore not allowing the sensor to work. Get someone to remove the valve clean it out, lube it and operate it a few times before re-installing.
Our one went through the start cycle then after about 30 seconds cut out, in the flight manual the is a section that gives the the start light sequence to help you diagnose.
Hope this helps
